Deutsche Bank signalled more jobs could be on the line after announcing plans to cut costs by €4.5bn (£3.6bn) a year and pledging to reduce bonuses to its most senior staff who will have to wait five years for any payouts.

The bank, which employs more than 8,500 personnel in the UK, is also setting up a new compensation standards panel to review the way staff are paid as it attempts to tackle the reputational challenges facing the banking industry amid an ongoing investigation into Libor rigging that cost Barclays £290m in fines.

In their 100-day review since being appointed co-chief executives, Jürgen Fitschen and Anshu Jain said they wanted to put the bank at the "forefront of cultural change in the industry".

"Tremendous mistakes have been made," said Jain, as he admitted that "highly paid individuals are our biggest cost base". However, with returns to shareholders falling, he added: "We can't expect our investors to allow us to pay the bonuses we have in the past."

Deutsche is to change its deferred bonus payouts to the top 150 staff and instead of staggered payments over three years – as has become a regulatory requirement following the 2008 banking crisis – there will now be a single payment after five years. London-based fund manager Hermes has led a campaign for changing pay at Deutsche, which did not put its remuneration policies to a shareholder vote this year.

The Libor scandal is also expected to reach Deutsche which admitted in July that some of its staff had been involved in trying to rig the key interest rates, although it insisted "no current or former member" of senior staff had been involved.

Jain described the Libor scandal as "a very grave matter ... It has shaken the banking industry to the core". In July, Deutsche had announced plans to cut 1,900 jobs outside Germany but more job cuts are now expected. Jain said that cost-cutting targets contained "scope for personnel reduction" although he also stressed that cost savings could be achieved in other ways as well.

In their strategy review, Fitschen and Jain said the bank was "committed to reducing bonus payments in relation to business performance". They did not name the "industry leaders, academics and compensation experts" which will sit on the panel to make recommendations on pay for the current 2012 financial year.

There was no guidance on the level by which bonuses may fall.

Jain and Fitschen replaced Josef Ackermann who stepped down in May after a decade at the top of Deutsche Bank.